Requirements for MCBCS is defined in SPWG, and in IEEE802.16e-2005 specification, two types of MBSs are supported: one is MBS accessed by a single base station (BS), and the other is MBS accessed by multiple BSs.
For the MBS accessed by multiple BSs which supports macro diversity, at least one centralized MBS wireless resource scheduler is required in the MBS Zone. At present, the Network Work Group (NWG) protocol has not involved how to implement MBS wireless resource scheduling, and has not involved how to allocate and describe wireless resources either. Although at present, a multicast and broadcast service wireless resource occupation description method is defined in the IEEE802.16e-2005 specification, this description method is not the optimum. New allocation and description methods should be applied in the network side to increase the efficiency of transmitting MBS resource scheduling information. Wherein:
SPWG: Service Provider Work Group, which is a work group in the WiMAX forum.
WiMAX: World Interoperability for Microwave Access.
MCBCS: Multicast and Broadcast Service (defined in SPWG), for which a service type is defined, that is, this service can be received by multiple users. When this service is borne on an air interface, it can be received by multiple users through respective one-to-one unicast with the plurality of receiving users, or it can be received by multiple users through one-to-many multicast and broadcast with the plurality of receiving users. Using the latter manner can save air wireless resources.
MBS: Multicast and Broadcast Service, for which an air interface bearer mode is defined. It means the MBS is sent in the air by using the same wireless resource, and can be received by multiple users. The MBS is classified into single-base station MBS and multi-base station MBS. The single-base station MBS means there is only one base station performing multicast and broadcast transmission, and the multi-base station MBS means there is multiple base stations performing multicast and broadcast transmission.
Macro diversity: a terminal receiving the same service from multiple base stations. The multi-base station MBS requires support of the macro diversity.
Slot: the minimal allocation unit of a data area in an Orthogonal Frequency Division Multiple Access (OFDMA) system, formed by consecutive sub-channels and consecutive symbols.
MBS Zone: a set of base stations, which transmit the same multicast and broadcast service and have the same multicast connection identification and security association.
SFN: Single Frequency Network.